Blind riveted joint



June 2, 1953 w c, HALE, JR 2,640,618

BLIND RIVETED JOINT Filed Jan. 13, 1950 vi F w) v INVENTOR! 71776017761 Haley/.3

' ATTORNEYS.

Patented June 2, 1953 BLIND 'RIVETED JOINT William 0. Hale, Jr Chester,zPa., assignor to 1 South Chester Corporatiomflhestcr, Pa., a corporation of Delaware Application January 13, 1950, SerialNO. 138,832'

2. Claims. (01.218-29) This invention relates to fastening devices in-.v tended for use-in permanently securing togetherstructural elements such for example as over lapped-plates or sheets. More particularly the invention is concerned with two element secur ins .devices. of :the general type disclosed in U. S. Patent No. 1,643,771 granted toJ, W. Ise-. man-on'Scptember 27, 1927, wherein an expander pinisdriven. into an axially socketed headed component having a shank, to spread the prongs at-the distal-slitted end portion of a shank. In such devices as ordinarily fabricated, the expanderpins are plain-surfaced and hence prone toislip out of place after a time, with the result thatthe headed components become loose by Weardueto vibration and therefore fail to maintain'the connected elements in rigidly secured relation. Moreover, with these prior art securins devices, pre-assembling of the component elements at the factory does not insure retainment of the pins by the headed components, andconsequently they must be re-assembled by the. user in the .field, which is annoying and time consumingespecially when the parts are. small and not readily handled.

Mylinvention has for its chief aim to overcome the above mentioned drawbacks which objective is realized in practice, as hereinafter more fully disclosed,-through provision of a fastening device.

oftthe type referred to, wherein the expander Din is. soiconstructed as to be self retaining after bein initially assembled with the headed component at the factory for the market, and which in being driven home incident to application of the device, will. cause the shank of said component to be circumferentially expanded into pressuroen agement with the walls of registering apertures in the parts being connected, and the prongs to be concurrently spread to rigidly unite said elements, with the parts of the device so incorporated as to be immune against loosening orayieldingto wear under vibration.

Other objects and attendant advantages of my invention will appear from the following detailed description of the attached drawings, wherein Fig; l is a view partly in elevation and partly in axial section,-of a fastening device conveniently embodying my'invention, with its components pre-assembledand ready for use.

Fig. 2 showsthe elevation of the rear end of the assemblage.

Fig. 3 is a cross section taken as indicated by the angled arrows III-III in Fig. 1.

Fig. 4 is a fragmentary view in section showing how the device is intended to be used, with theexpander component part way advanced in.

the maincomponent.

Fig. .5 is a section taken as. indicated. .bythe:

angled arrows V-V in Final; and

Fig. 6 is a view. correspondingto Fig. 4, showing; theexpanding elementin its final positioninthc;

rivet component.

With :more. detailed referenceto. these: illus-n tratlons, the letter .A comprehensively. designates: the. main component which in practice: isiiaslr-l; ioned from; relatively soft: metal. such. 35560111381? or aluminum, and B. the expander component: which is fashioned from. hard metal suchfasr steel, these components being.-preassembledzlion marketing inthe relation shown in Fig.1.

prongs. 6 for a purpose later :on explained. :1.

The expander-component B is in the dorm tor: a pin whereof the diameter corresponds to that; of the bore 3 in the headed component: .A,.1.th'e.'

outer end of the pin being square cut as .at u'l, and the inner; end 8 being roundpointed: and

tapered at a sharpangle ascompared:with:.that1 of the recessed bottom t ofthe socket borexofqthez component A- V section grooves 9 (in this;

instance, three). are formedlongitudinallyin:

the piniB at oircumferentiallyrspaced intervals; inl-such :a way as to'provide relatively sharp; paralleled. lengthwise ridges i ii to extend somewhat beyondithe oylindric surface of saidshank asshown in Fig. 3. It is to be especially observed:

that the slots .9 and the ridges-ill terminatetwell short of the :endszof .the .cylindric portion :ofcthe: pin In, practice, the componentiA .made. from a relatively soft metal and the-component LB.

froma metal-.muchw-harder byv comparison. for; a reason-which will be presently understood. .3

To. assemble theparts for marketing in roadie. ness foruse, the split .end of the shank 2. of the. component A is clinched to collapse the prongs asshown-i Fig. 1, and thepinB is forced. into.

the bore 3 of saidcomponent until the rounded.

tip ofitstapered end 8 justabout contacts .the. bottom .4 of said bore. ,In carryingoutthelatter step, the shank 2 of; component. A is held to-its.

true cylindric form by a suitable constraining means (not illustrated) so that the amount of the soft metal of the shank displaced by the action of the ridges I on the pin B is forced into the troughs of the V grooves 9, as at H in Figs. 1 and 3. Subsequent disassociation of the two components when so assembled cannot therefore occur either before or during application of the device in practice.

When the device is used, for example, to secure together two overlapped plates or the like P, P as in Figs. 4 and 5, the shank 2 of the headed component A is passed through registering apertures of slightly larger diameter in said plates (this operation being facilitated by the slight taper of the shank efiected by collapsing of the prongs 6 at its split end) until the back of the head 2 bears against the outer plate P. With this accomplished, the protruding end of the expander pin B is struck one or more blows, as may be necessary, with a hammer or other suitable tool, until fully driven into the component A. As the pin B advances, in Fig. 4, a portion of the metal of the component A, previously forced into the grooves 9 during assembling as above explained, is displaced outwardly at the regions l2 by the outer end shoulders I3 of said grooves, while, by the action of the ridges l0, the-shank 2 is circumferentially expanded into pressure engagement with the walls of the apertures in the plates P, P as exaggeratedly shown at the regions M in Fig. 5. At the same time, the split end of the shank 2 is expanded through camming action between the rounded sharply tapered end 8 of the pin B and the coned bottom of bore 3 in the rivet component A and the prongs 6 thereby bent outwardly behind the plate P. When the pin B is driven home with its square end flush with the outer face of the head i as in Fig. 6, the plates P, P will be rigidly clamped together between said head and the outwardly spread prongs 6, and the pin will be effectively secured against rotation within the shank as well as against dislodgment endwise clue to displacement of the metal of the shank into the grooves 9 at I I. Moreover, by reason of the dilation of .the shank into pressure engagement with the inner surfaces of the apertures in the plates attainment of maximum efli-ciency of the device in actual use. For best results, the dimension from the square end I of the pin B to the front ends of the grooves 9 should not be in excess of half the diameter of the pin, but should be at least of the diameter of the pin. The depth of the bore 3 in the component A should be somewhat in excess of the combined thickness of the plates or elements P, P' which are to be connected. The length of the pin B should not appreciably exceed the length of the rivet component A in order to avoid undue projection of its tapered end 8 beyond the prongs 6 when the latter are fully spread as in Fig. 6. It is to be understood that the length of the grooves 9 (and of the ridges ID) of the pin B are varied in accordance with the metal from which the rivet componentA is made. Thus if the metal of the component A is relatively soft and hence easily displaced, the length of the grooves 9 may be equal approximately to the length of the shank 2 from the inner surface of the head to the point at which the prongs 6 commence to spread as shown in Fig. 6. When harder metals, more resistant to easy displacement, are used for the headed component A, the grooves 9 in the pin B must be made shorter so that less metal is displaced and breaking down of the ridges l0 avoided during driving of the pin as the device is applied.

Having thus described my invention, I claim:

1. In combination an expanding rivet consisting of a head, a shank with a longitudinally split end portion and an axial cylindrical socket bore terminating short of the distal end of the shank; and an expander pin of substantially the same diameter as the bore consisting of a cylindrical portion and a tapered end portion, said expander pin being of a harder material than said shank and having substantially three relatively narrow, longitudinal, circumferentially spaced V-grooves and associated ridges formed therein in the central longitudinal portion of the cylindrical portion thereof whereby integral ridges are formed adjacent each groove on either side thereof, said pin terminating at a distanceposition wherein the end of the pin is flush with the head. 7

2. In combination an expanding rivet consisting of a head, a shank with a longitudinally split end portion and an axial cylindrical socket bore terminating short of the distal end of the shank and an expander pin of substantially the same' diameter as the bore consisting of a cylindrical portion and a tapered end portion, said expander pin being of a harder material than said shank and having substantially three relatively narrow, longitudinal, circumferentially spaced V-grooves and associated ridges formed therein in the central longitudinal portion of the cylindrical por-' tion thereof whereby integral ridges are formed adjacent each groove on either side thereof, said pin terminating at a distance from said grooves and ridges substantially equal to the thickness of said head, the unslitted portion of the shank being circumferentially expanded in the region corresponding to said grooves and ridges and said split end portion being expanded along the tapered portion and ungrooved distal portion of said pin, and a plurality of plates or the like bound between the head and the expanded split end of said shank.

WILLIAM C. HALE, JR.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain Aug. 8, 1944 

